There are a lot of differing opinions out there, educated and otherwise, on just how much performance-enhancing drugs actually enhance performance. On the one side, there’s suspected users like Barry Bonds and Roger Clemens pulling off incredible feats at advanced ages. On the other, there’s the long list of proven cheaters littered with names of journeymen long forgotten.

Now, though, that long list has suddenly gotten interesting at the end. The last three veteran major leaguers caught cheating were all exceeding expectations in a pretty big way:

– Melky Cabrera, the 2012 All-Star Game MVP, was leading the NL with a .346 average through 113 games when he was suspended. His OPS went from .671 in 2010 to .809 in 2011 to .906 last season.

– Bartolo Colon had a 3.43 ERA in 24 starts for Oakland prior to his suspension. Two years after his career was presumed over due to shoulder problems, he was on his way to his best season since 2005. Had he maintained the 3.43 ERA, it would have been his second-lowest mark in 15 big-league seasons.

– Carlos Ruiz established new career highs in average (.325), homers (16) and RBI (68) as a 33-year-old last season. The homer total was two more than he had the previous two seasons combined. His .540 slugging percentage was almost 150 points higher than his career mark of .393.

Of course, Ruiz, unlike the other two, wasn’t caught with testosterone. And because he was using an amphetamine, not a steroid, he’s getting just a 25-game suspension (Cabrera and Colon received 50 games apiece).

Whether the Adderall deserves any credit for Ruiz’s performance spike is a matter I’ll let others debate. But it’s more ammunition for those who believe that cheaters get an incredible advantage over those who get their results naturally.